The Good Question and My Answer.

[rwh11385]

So was it a sparco bar... or a IE knockoff?

There are a lot of bent e30s out there...

I used sparco bars until I had an e30 on a 7 post chassis shaker and actually saw what was going on with them in real time (actually broke a Sparco knock off and the BMP bar).

After that I got togeather with John to really solve the problem.

Eh, doesn't really matter, you'll never redeem yourself no matter what to the BMW community and be as big of a joke as Budget Beater or Jordan Sarette.

[kishg]

ok, i'll bite DC. Can we see the original measured data? and what range is within normal operating parameters and what is beyond, like when on a track? that would determine if your braces and bars actually have a practical benefit or are overkill wouldn't it?

[z31maniac]

No, into losing your patience.

[DCColegrove]

This should be good...

This is a useful contribution to this discussion?

Or is you point to bait me into loosing my patience.

[direction88]

This should be good...

[DCColegrove]

This would go a lot smoother without the "noise".

This was posted by me a while ago on comparing front stress bars:

mounted as intended the sparco bar was bitchin good at controlling flex of the strut towers in and away from each other. Not so good in controlling front to back (twisting) At the top end of knocking the shit out of the chassis on the shaker it allowed just over 22mm of this motion (total measured at the top of the struts)



The bar (fabricated by John) we are using now only allowed 7mm same program same chassis (swapped/tested...swapped/tested 3 iterations in a row)

[atomic]

oh Lord!

3rd


edit--- hopefully there will be some useful info to come from this....

:up:

[Farbin Kaiber]

*White Noise*

[z31maniac]

First.

[DCColegrove]

I don't know when you came into this but the discussion has a lot of history...

I'm probably at the end of my rope with it for many reasons... and have been extreamly short whith my detractors for a while now.

However...

I do not mind answering an honest question here (also sent you via PM)

I´m so assuming you took the chassis and BENT it in a bench and derived all your construction parameters from there.

i.e the bending stresses and how much angular movement there was with x amount of force to the shock towers and subframe and where thus able to find the the ideal bracing to stop the chassis from bending. Or did you just weld some stuff in a few times to make it stop bending?

There is a difference between imperical "engineering" (fiddling) and engineering (good old math)
I´m all for discussion , but only when people answer with discussion and not little remarks.

I wasted a lot of typing on it though then the thread was locked…. I’ll start over.

My job a long time ago was to dream up ways to test what engineering came up with… To shake out unforeseen failures diagnose the cause and help correct them… I’m not saying the math was wrong I’m saying that there is LUC (Law on unintended consequences) no matter how many times you run numbers something in real life will break...

But… Yes you assumed correctly on both counts… both empirical (fiddling) and hard math engineering (math mostly already done for me).

The original measured data was derived from a raw e30 on a 7 post (7 plane) Chassis shaker… At this same time the effectiveness of several braces were tested.

I had the luck and luxury to borrow this machine because the owner is a friend who was exceptionally helpful in bringing me up to speed on modern telemetry and data collecting methods.

My original intent was not to sell bars or anything else to anyone... We were just curios. But then I went on a mission after what we found...

These braces are designed and have been tested to directly address chassis flex that was measured on that chassis shaker… And also tested for any unintended results of mitigating the flex we set out to mitigate.

I have posted some of the actual data here on R3V somewhere… I’ll dig some of it up again if you can’t find it.

These braces (front Strut, Lower X, Rear Brace system) are not “ideal” in the strict sense but as ideal as a bolt on assembly can be to mitigate undesirable chassis component compliance. They are an alternative to building a full on GT2 (or what have you) for the guy out there that doesn’t want to gut his car and weld in structural bracing.